Blood components are red cells, white cells, platelets and plasma. These can be put to different uses.
RED BLOOD CELLS
Red blood cell also known as erythrocytes make up 45% of blood volume lacks nucleus and contains the oxygen-carrying protein haemoglobin, which is a pigment that gives whole blood its red colour. Erythrocytes are produced inside of red bone marrow. Its main function is to distribute oxygen to body tissue, and carry waste carbon dioxide back to lungs. In addition to its key role in transporting oxygen and carbon dioxide, haemoglobin also plays a role in the regulation of blood flow and blood pressure.
WHITE BLOOD CELLS
White blood cells also known as leucocyte, make up a tiny fraction of whole blood. White blood cells have nuclei and full complement of other organelles but do not contain haemoglobin. The main function is to fight infection and are part of the body defence system. There are five types of leucocytes divided into two major classes which are granular and agranular leucocytes. Granular leucocytes includes neutrophils, eosinophils and basophils. Neutrophils contains digestive enzymes that neutralises bacteria that invade the body. Eosinophils contains digestive enzymes specialised for digesting viruses that have been bound to by antibodies against infections by pathogens. Basophils have a pale nucleus that is usually hidden, by granules they secrete histamine which increases tissues blood flow via dilating the blood vessels, and also secrete heparin which is an anticoagulant that promotes mobility of other white blood cells by preventing clotting. Agranular leucocytes includes lymphocytes and monocytes. Lymphocytes (T cells, B cells and natural killer cells) mediate immune responses, including antigen-antibody reactions. B cells develop into plasma cells, which secrete antibodies. T cells attack invading viruses, cancer cells, and transplanted tissue cells. Natural killer
Bibliography: Tortora, G.J., Derrickson, B., 2011., Principles of Anatomy & Physiology. 13th ed. Asia. John Wiley & Sons Pte Ltd Starr, C., McMillan, B., 2001, Human Biology. 4th ed. USA. Wandsworth Group www.hccfl.edu/media/374631/ch_22_summary.doc pp 830-834, fig 22.20-22.22 (accessed 28 May 2014)